Field of Invention
This invention relates to a vehicle cooling system. More specifically, this invention relates to an air cooling arrangement on an agricultural vehicle.
Description of Related Art
Agricultural vehicles, such as agricultural tractors require a number of radiators in order to cool working media, such as a water cooler for the engine, a transmission oil cooler, a hydraulic oil cooler, an intercooler and possibly a condenser for an air-conditioning system. It is common practice to arrange the radiators in series one after the other under a bonnet of the vehicle so that air from a fan positioned at the front of the vehicle drives air through the series of radiators. Radiators in this arrangement, however can result in creating a high resistance to air flow. To overcome the resistance, a larger fan may be required. The radiator arrangement may also interrupt the air flow resulting in overheating of the radiator or radiators.
A tractor driver must be able to see the implements attached to the front of the vehicle from the driver' seat which means the front bonnet must not be too high or long. There is also a desire for the front wheels of the vehicle to be steered as tightly as possible. For the front wheels to be able to turned as far as possible, the bonnet of the vehicle, in which the radiator sub-assembly is arranged, must be kept as narrow and low as possible. The radiator sub-assembly is therefore subject to substantial restrictions with respect to its dimensions particularly in width and height. Since the heat sink of the radiators cannot therefore be substantially increased, dissipation of the resultant waste heat presents difficulties, particularly because of the trend to constantly increase the drive power of the vehicle. In order to obtain satisfactory heat dissipation, the radiators are usually arranged in as series at different heights.
It is known to fix radiators to a carrier plate which is mounted to the tractor chassis. EP1849684 discloses a carrier plate which is fitted directly in front of the engine on an approximately horizontal level between two longitudinal frames of the chassis in the front axle region of the vehicle. Radiators are arranged on the plate in a series with the radiator nearest the engine being mounted on a lowered step of the plate to enable a taller radiator to be mounted. Such an arrangement does not optimise the air flow through the radiators and may necessitate a larger fan to obtain the desired air flow.